You must acknowledge that real-time measurements using GNSS technology may be affected by a number of factors that are not under the control of the operator performing the measurements or the reference station network administrator.
Examples of such external factors can be:
- false information in messages transmitted by GNSS satellites. There are (very rare) situations where, at some point, one or more satellites in a particular constellation can transmit false information. Errors caused by satellite orbits or clocks may usually occur. More information about satellite constellations and the status of their satellites can be found by visiting the websites dedicated to satellite navigation systems, respectively for the NAVSTAR GPS System https://www.navcen.uscg.gov/?Do=constellationStatus, for the GLONASS System https://www.glonass-iac.ru/en/GLONASS/, for the GALILEO System https://www.gsc-europa.eu/system-service-status/constellation-information, and for BeiDou ttps://www.glonass-iac.ru/en/BEIDOU/
- reflections of satellite signals, an effect described in the specialty literature as "multipath". This involves the reception by the rover antenna of additional signals, reflected by flat surfaces or other objects nearby, such as: concrete or metal walls, metal roofs, metal pillars, water gloss, etc.;
- possible jamming sources in the area, such as: transformer stations, high or medium voltage lines, various high-power emission antennas (radars, GSM relays, radiocommunications, etc.);
- atmospheric disturbances, the ionosphere in particular. These can be checked by accessing the following link: https://rompos.ro/index.php/en/technical-info/nova-maps
- possible malfunctions of one or more GNSS reference stations in the area at the time. The functionality of server communications and GNSS reference station communications can be verified by accessing the following link: http://rtk.rompos.ro/.
Also, a possible incorrect setting of the rover should not be ruled out. In this respect, it is useful to recheck the settings of the device and eventually reconfigure the NTRIP profile.
Regarding the problem of solution fixing, please also read the information in the link: https://rompos.ro/index.php/en/f-a-q/rompos-f-a-q/i-can-t-connect-the-gnss-equipment-to-rompos-what-could-be-the-cause